Facsimile recording blank



Aug. 25, 1942. B. L. KLINE 2,294,150

FACSIMILE RECORDING BLANK Filed Feb. 16, 1939 FIG. I

CON DUCTING PAPER vINVENTOR BERNARD L. KLI NE BY Patented Aug. 25, 1942 OFFICE FACSIMILE RECORDING BLANK Bernard L. Kline, Manhasset, N. Y., assignor to The Western Union Telegraph Company, New York, N. Y., a corporation of New York Application February 16, 1939, Serial No. 256,677

8 Claims.

The present invention relates to novel and improved means for electrically recording visible marks on a recording surface and more particularly to the production of a novel pigment coated recording sheet especially suited for the reproduction of pictures by. facsimile methods.

The principal object of the present invention is to provide improved electrical recording blanks so that pictures may be reproduced accurately, clearly and in permanent form.

Another object of this invention is to provide improved white and colored compositions for facsimile blanks of the type employing a conducting paper base. f

Further and more specific objects will appear in the following disclosure of the invention in its several aspects.

Referring to the drawing:

Fig. 1 illustrates diagrammatically a facsimile system embodying transmitting and recording means, this system. being of the type employing a simple receiver in which a telegraphic blank embodying the present invention may be used.

Fig. 2 is a perspective view of a receiving blank embodying the invention.

The invention embracing novel coating materials and compositions, will be disclosed in detail in connection with a description of Fig. 2 of the drawing, which shows a recording blank l which comprises a sheet of'fibrous material II composed preferably of paper containing distributed particles of conducting material such as carbon, a metallic powder or suitable mixture thereof. The particles may be introduced into the paper pulp during manufacture of the paper or the sheet after fabrication-may be impregnated therewith. This sheet of paper containing solid conducting particles has considerably less electrical resistance than ordinary paper and will readily conduct electric current when potentials suitable for facsimile recording are applied to it. The contrasting pigment I2, which is applied to the paper as a thin masking layer in accordance with the present invention,

' preferably includes an appreciable quantity of zinc sulphide either alone or mixed with other substances in a manner to be disclosed. Zinc sulphide because of its extremely high opacity may be applied in a very thin layer thereby enabling recording to be effected at low applied potentials, as will hereinafter appear. Also, due to its blue white color and high light reflecting property, better contrast with the marking carbon particles is obtained than in the case of whites of a yellowish tinge. Its blue white color,

moreover, is permanent, not turning dark or yellow with age, and is not readily-oxidized. Thus it retains its original high masking and high contrast properties. Unlike 'such pigment as white lead, lead sulphate, titanium dioxide and barium sulphate, it neither melts nor decomposes at high temperatures but sublimes. Its sublimation temperature of 1180 0., being far below the local heat generated adjacent thevpoint of the recording stylus, when marking potential is applied thereto, may account for the sharp images obtained with this material. Zinc sulphide is highly desirable, also from the standpoint of its applicationto the conducting base or sheet. It is non-toxic, relatively inexpensive, and has good working qualities. Due to its low specific gravity (4.1) as compared with most white pigments, it more readily stays in suspension in the vehicle employed and is especially suitable for use in lacquers, such as those composed of cellulose derivative lacquers, hydrocarbon resins, shellac dissolved in alcohol, ester gums, natural varnish gums, polyvinyl resins, etc., in suitable solvents. Suitable solvents for such resins and gums are ester solvents, such as ethyl, butyl and amyl acetates, butyl lactate and Cellosolve hydrocarbon solvents such as mineral spirits, toluol, etc.;

I and alcohol type solvents, such as -'isopropyl and ethyl alcohol. In fact, due to its inert nature it is susceptibleto use inan unusually wide variety of vehicles and binders, others which may be mentioned being such oils as linseed, tung, perilla, fish, soya bean, etc. It spreads evenly enabling coatings of uniform desired thickness to be readily obtained in a single application, especially when applied as a lacquer.

Where the pigment of the invention ismixed in a drying oil, such as linseed oil, with the addition, if desired, of some thinner, gums or resins, the resulting ink closely resembles a printing ink and'the contrasting layer I2 may be readily applied, by employing ordinary printing methods, from the cylinder, blanket or other printing member of an ordinary printing press.

' Suitable thinners which may be used are turpenis desired in order to provide greater covering.

power, it may be applied in several thin coats by successive printing operations since this results in a more even application of the coating material. In practice it was found that excellent records were obtained by coating conducting carbon bearing paper with single or plural coats of an ink composed of zinc sulphide ground in suitable oil.

In place of using zinc sulphide alone as the masking pigment, other pigments may be added thereto in various proportions, either to modify the color of the coating or its covering power. For instance, barium sulphate added to the zinc sulphide materially increases its masking property. Cadmium lithopone may also be added. This latter pigment is of a yellow color and admixed with the zinc sulphide produces a golden yellow coating on the blank having high contrast with the black carbon impregnated sheet. Other good masking pigments, such as titanium dioxide, zinc oxide, lead oxide, mercuric sulphide, etc., mixed with zinc sulphide, may be used. Excellent results in practice were obtained with approximately 25% of zinc sulphide and 75% of Vermilion mercuric sulphide. It will be understood, however, that these proportions are not critical and the percentage of each constituent used will be determined by the desired color of the background, the masking property of the mixture and its contrast with the color of the conducting sheet on which it is applied. 7

It will be apparent to those skilled in the art that the conducting paper I I may be coated with a layer I! which comprises superimposed coats of one or more of the above disclosed masking materials, for example a coating of vermilion mercuric sulphide may be covered with a coating of zinc sulphide or this arrangement of the layers may be reversed. Different colors or shades of the background against which a record appears are readily obtained by varying the thickness of one or more of the coatings or by reversing the order in which they are applied. Whether applied in a single layer or in a plurality of superimposed layers, I prefer that the film or coating produced on the base ll shall be of a thickness between 0.00008 and 0.00015 inch. With thinner coatings it is diificult to obtain the necessary masking of the supporting sheet, and with heavier coatings the definition of the recording is less sharp. With the coating of the present invention applied within the range specified, scanning may be effected with a tracing of one hundred or more lines per inch, while maintaining each line clear and distinct. The coating, moreover, is extremely sensitive to the applied potential and may be scanned at high speed with applied potentials of the order of magnitude of 300 volts.

Fig.1 of the drawing shows a conventional facsimile system of the form disclosed in the appli-- cation of R. J. Wise, Ser. No. 23,926, filed May 28, 1935, which may be used for transmission of pictures for recording on the improved blank of the present invention. Referring to Fig. 1 the scanning electrode or stylus [4, the point of which bears on the surface of a blank I), bearing a picture reproduced in conductive ink, is supported by a travelling carriage l adapted for longitudinal movement. The stylus I4 is caused to traverse the cylinder in a longitudinal manner by any suitable means, for example the lead screw l6, and therefore the stylus point will describe a helical path as it moves over the sur face of the transmitting blank and thus produce a scanning action. Likewise in the receiving device shown at the right hand side of Fig. 1 of the drawing, the cylinder I! is rotated and the receiving stylus I8 is advanced longitudinally of the cylinder, so that it traverses the blank with a helical movement covering all parts of the blank by a series of parallel lines. It will be understood that any suitable receiver or recording device may be employed, it being preferred, however, that the receiving device have a platen or cylinder of relatively large area with respect to the stylus l8 which has a fine point.

The method of practicing the invention will be understood clearly from the foregoing, but briefly it comprises placing a blank, prepared in the manner disclosed in connection with the description of Fig. 2, on a platen such as the cylinder I! of Fig. 1. The stylus 18, which traverses the platen in synchronism with the scanning device of the transmitter, such as the stylus I4, is supplied with signals representing progressive points of the picture or other subject matter appearing on the sheet I). These electrical signals of varying intensity are applied through the blank I0 between the platen l1 and the stylus l8 and appear to remove portions of the coating of the masking pigment l2 beneath the stylus. The marking, however, produced, occurs in proportion to the intensity of the applied potential and thus results in an accurate reproduction on the blank of the picture or other subject matter transmitted.

The nature of the invention will be determined from the foregoing and the scope thereof is defined in the appended claims.

What is claimed is:

1. A record blank for visual recording in response to electric potentials applied locally thereto, said blank being adapted to display the record immediately upon passage of current and without further treatment, said blank comprising a supporting sheet of conducting material having a thin masking coating thereon of a contrasting color comprising zinc sulphide, the masking coating having the characteristic of being removable from selective elemental areas of the blank to expose the background of the blank by electrical marking potentials applied to said elemental areas of the blank when it is scanned by a recording stylus, said zinc sulphide being present in said coating in an amount sufficient to effect volatilization in said selected elemental areas and facilitate sharp definition of the recorded subject matter.

2. A record blank for visual recording in response to electric potentials applied locally thereto, said blank being adapted to display the record immediately upon passage of current and without further treatment, said blank comprising a supporting sheet of conducting material and a thin mask on said support of a contrasting color comprising zinc sulphide and cadmium lithopone, the masking coating having the characteristic of being removable from selective elemental areas of the blank to expose the background of the blank by electrical marking potentials applied to said elemental areas of the blank when it is scanned by a recording stylus, said zinc sulphide being present in said mask in an amount sufficient to effect volatilization in said selected elemental areas and facilitate sharp definition of the recorded subject matter.

3. A record blank for visual recording in response to electric potentials applied locally thereto, said blank being adapted to display the record immediately upon passage of current and without further treatment, said blank comprising a layer of a carbon bearing conducting sheet and an opaque film of contrasting color on the exposed surface of said sheet, said film including zinc sulphide incorporated with a binder, said opaque film having the characteristic of being removable from selective elemental areas of the blank to expose the background of the blank by electrical marking potentials applied to said elemental areas of the blank when it is scanned by a recording stylus, said zinc sulphide being present in said film in an amount sufiicient to effect volatilization in said selected elemental areas and facilitate sharp definition of the recorded su -ject matter.

4. A record blank for visual recording in response to electric potentials applied locally thereto, said blank being adapted to display the record immediately upon passage of current and without further treatment, said blank comprising a support of conducting sheet material and a thin mask on said support of a contrasting color comprising zinc sulphide and a pigment which increases the opacity of said mask, the masking coating having the characteristic of being removable from selective elemental areas of the blank to expose the backgroundof the blank by electrical marking potentials applied to said elemental areas of the blank when it is scanned by a recording stylus, said zinc sulphide being present in said mask in an amount sumcient to effect volatilization in said selected elemental areas and facilitate sharp definition of the recorded subject matter.

5. A record blank for visual recording in response to electric potentials applied locally thereto, said blank being adapted to display the record immediately upon passage of current and without further treatment, said blank comprising a support of conducting sheet material and a thin' mask on said support of a contrasting color comprising zinc sulphide mixed with barium sulphate, the masking coating having the characteristic of being removable from selective elemental areas of the blank to expose the background of the blank by electrical marking potentials applied to said elemental areas of the blank when it is scanned by a recording stylus, said zinc sulphide being present in said mask in an amount sufiicient to effect volatilization in said selected elemental areas and facilitate sharp definition of the recorded subject matter.

6. A record blank for visual recording in response to electric potentials applied locally thereto, said blank being adapted to display the record immediately upon passage of current and without further treatment, said blank comprising a support of conducting sheet material and a plurality of superposed films on said support, each film comprising zinc sulphide incorporated with an adhesive binder, said films having the characteristic of being removable from selective elemental areas of the blank to expose the background of the blank by electrical marking potentials applied to said elemental areas of the blank when it is scanned by a recording stylus, said zinc sulphide being present in said film in an amount sufiicient to effect volatilization in said selected elemental areas and facilitate sharp definition of the recorded subject matter.

'7. A record blank for visual recording in response to electric potentials applied locally thereto, said blank being adapted to display the record immediately upon passage of current and without further treatment, said blank comprising a support composed of sheet material containing distributed solid conductive particles, and a thin masking coating thereon of a contrasting color, comprising zinc sulphide incorporated with an adhesive binder, the masking coating having the characteristic of being removable from selective elemental areas of the blank to expose the background of the blank by electrical marking potentials applied to said elemental areas of the blank when it is scanned by a recording stylus, said zinc sulphide being present in said coating in an amount suilicient to effect volatilization in said selected elemental areas and facilitate sharp definition of the recorded subject matter.

8. A record blank for visual recording in response to electric potentials applied locally .thereto, said blank being adapted to display the record immediately upon passage of current and without further treatment, said blank comprising a support of conducting sheet material and a thin mask of a contrasting color on said support comprising zinc sulphide and titanium dioxide, both of said ingredients being incorporated with an adhesive binder, the masking coating having the characteristic of being removable from selective elemental areas of the blank to expose the background of the blank by electrical marking potentials applied to said elemental areas of the blank when it is scanned by a recording stylus, said zinc sulphide being present in said mask in an amount sufiicient to effect volatilization in said selected elemental areas and facilitate sharp definition oi the recorded subject matter.

BERNARD L. KIINE. 

